WISC‐IV and low IQ: review and comparison with the WAIS‐III

The WISC‐IV is likely to be in common use for the assessment of children with low intellectual ability for the next 10–12 years. There are several concerns about its uses with these children. Some children may not understand the instructions on some subtests, notably for letter‐number sequencing. There may be an unacknowledged floor effect that will result in an overestimate of intellectual ability. The percentile ratings given in the manual are inaccurate for percentiles below 1%. Evidence is presented that the WISC‐IV may systematically give lower IQ scores than the WAIS‐III when assessing low IQ.

[1]  Kay E. Ketzenberger,et al.  American Association on Mental Retardation , 2008 .

[2]  S. Whitaker,et al.  The Distribution of Scaled Scores and Possible Floor Effects on the WISC-III and WAIS-III , 2008 .

[3]  S. Whitaker The uses of the WISC-III and the WAIS-III with people with a learning disability: Three concerns , 2005 .

[4]  S. Whitaker Should we abandon the concept of mild learning disability , 2003 .

[5]  Muriel D. Saunders,et al.  Mental retardation: Definition, classification, and systems of supports , 2003 .

[6]  Robert L. Schalock,et al.  Mental Retardation: Definition, Classification, and Systems of Supports , 2002 .

[7]  Timothy R. Konold,et al.  Factor Replication of the WISC-III in Three Independent Samples of Children Receiving Special Education , 1997 .

[8]  Nel Roeleveld,et al.  The prevalence of mental retardation: a critical review of recent literature , 1997, Developmental medicine and child neurology.

[9]  H. H. Spitz Variations in Wechsler Interscale IQ Disparities at Different Levels of IQ. , 1989 .

[10]  H. H. Spitz Disparities in mentally retarded persons' IQs derived from different intelligence tests. , 1986, American journal of mental deficiency.

[11]  J. Flynn,et al.  Wechsler Intelligence Tests: do we really have a criterion of mental retardation? , 1985, American journal of mental deficiency.

[12]  S. A. Richardson,et al.  Epidemiology of severe mental retardation in children: community studies. , 1975, American journal of mental deficiency.

[13]  E. R. Johnstone Variations in Wechsler Interscale IQ Disparities at Different Levels of IQ , 2002 .

[14]  Dc Washington Diagnostic and Statistical Manual of Mental Disorders, 4th Ed. , 1994 .

[15]  Robert I. Watson,et al.  The Wechsler-Bellevue Intelligence Scale. , 1951 .